What is LHC@home?

This a volunteer computing project that uses Internet-connected computers to advance Particle and Accelerator Physics. Participate by downloading and running a free program on your computer. By default, you can run the classic LHC@home application Sixtrack, for simulations of accelerator physics, and help researchers at CERN to improve the LHC.

Other LHC@home simulations that utilizes virtualization to run applications for Theory and experiment simulations for ATLAS, CMS and LHCb are also available.

We decided to deliver a presentation every day in the most populated time slots out of the doodle poll, i.e. on Sat. 14th Sep, between 03:00 and 04:00 PM, and on Sun 15th Sep, between 02:00 and 03:00 PM.
The meeting point will be the LHC@Home desk in R2 (building 504), at the beginning of the time slot. We will have to walk few minutes to a meeting room where there will be the presentations. We will be back at the meeting point by the end of the time slot at the latest.

Many queued tasks - server status page erratic
Due to the very high number of queued Sixtrack tasks, we have enabled 4 load-balanced scheduler/feeder servers to handle the demand. (Our bottleneck is the database, but several schedulers can cache more tasks to be dispatched.)

Our server status page does not currently show in real time the daemon status on remote servers. Hence the server status page may indicate a varying number of processes, depending on which web server is active.

Please also be patient if you are not getting tasks for your preferred application quickly enough. After a few retries, there will be some tasks. Thanks for your understanding and happy crunching!

CMS@Home disruption, Monday 22nd July
I've had the following notice from CERN/CMS IT:

>> following the hypervisor reboot campaign, as announced by CERN IT here: https://cern.service-now.com/service-portal/view-outage.do?n=OTG0051185
>> the following VMs - under the CMS Production openstack project - will be rebooted on Monday July 22 (starting at 8:30am CERN time):
...
>> | vocms0267 | cern-geneva-b | cms-home

to which I replied:> Thanks, Alan. vocms0267 runs the CMS@Home campaign. Should I warn the volunteers of the disruption, or will it be mainly transparent?

and received this reply:Running jobs will fail because they won't be able to connect to the schedd condor_shadow process. So this will be the visible impact on the users. There will be also a short time window (until I get the agent restarted) where there will be no jobs pending in the condor pool.
So it might be worth it giving the users a heads up.

So, my recommendation is that you set "No New Tasks" for CMS@Home sometime Sunday afternoon, to let tasks complete before the 0830 CST restart. I'll let you know as soon as Alan informs me that vocm0267 is up and running again
17 Jul 2019, 13:14:12 UTC
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